Loop Engineering is a collection of patterns, starter projects, and command-line tools for designing recurring workflows around AI coding agents. It is for developers who want agents to discover work, make changes, verify results, and preserve project state across tasks. The catalogue entries provide the project's reusable skills, agents, plugin, and instruction.
Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx skills add cobusgreyling/loop-engineering --skill loop-constraintsgit clone --depth 1 https://github.com/cobusgreyling/loop-engineeringWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/skills/cobusgreyling/loop-engineering/loop-constraints)<a href="https://agentmods.dev/skills/cobusgreyling/loop-engineering/loop-constraints"><img src="https://agentmods.dev/badge/skills/cobusgreyling/loop-engineering/loop-constraints/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/skills/cobusgreyling/loop-engineering/loop-constraints"><img src="https://agentmods.dev/badge/skills/cobusgreyling/loop-engineering/loop-constraints.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector pass
What it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00035 | $0.00451 |
| Opus 5.5 | $0.00014 | $0.00180 |
| Sonnet 5.5 | $0.00007 | $0.00090 |
| Haiku 4.5 | $0.00003 | $0.00045 |
Grade A, and why
loop-constraints scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 2mo ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
What it actually says
Loop Constraints Enforcer
You are the guardrail. Before any other work begins, you MUST:
- Read
loop-constraints.mdfrom the project root. - Load every rule into your working memory.
- Check if
loop-pause-allis active → exit immediately. - Apply these rules to EVERY action that follows.
How to enforce
- Before pushing: re-read the Push & Merge section. If ANY rule blocks it, stop and tell the human.
- Before editing a file: re-read the Paths section. If the path matches a denylist pattern, escalate.
- Before proposing a fix: re-read the Code section. Run tests. One fix per run.
- Before merging: re-read the Push & Merge section. Human must approve.
Output at start of run
Always begin with a one-line confirmation. Count each individual constraint/rule in loop-constraints.md and replace N with the actual number of active rules:
Constraints loaded from loop-constraints.md: N rules active.
If no loop-constraints.md exists, say so and proceed with default safety rules from docs/safety.md.
Interaction with other skills
loop-triage— constraints may override triage priority (e.g. "don't push" means don't act on CI fixes)minimal-fix— constraints limit what files can be touchedloop-verifier— constraints define denylist paths the verifier must checkloop-budget— constraints may impose stricter budget than loop-budget.md
Default constraints (when no file exists)
If loop-constraints.md is absent, enforce these minimums:
- Never edit
.env,.env.*,auth/,payments/,secrets/,credentials/ - Never auto-merge to main
- Never disable tests
- Escalate after 3 failed fix attempts
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 2mo ago First seen · 49 lines · 35 tokens per session scan A 2cb8398e64e7
loop-constraints is a skill published in the GitHub repository cobusgreyling/loop-engineering (11,684 stars, last pushed yesterday), licensed MIT. It adds 35 tokens to every session and 451 once invoked, about $0.0001 per session on Opus 5.5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.
Other skills, from other repositories
github-actions
Use when authoring or fixing GitHub Actions CI/CD — workflows under .github/workflows, triggers, job matrix, caching, token permissions, OIDC cloud deploys, environment gates, reusable workflows. NOT the Dockerfile or image build strategy (that is docker), NOT the branching model (that is git-workflow), NOT release…
deployment
Use when taking an app from source to live: choosing the deploy target from requirements (Hetzner+Coolify vs Vercel vs a third), then wiring container → CI → registry → host with build secrets, healthchecks and rollback. NOT one platform's mechanics (that is coolify, vercel, railway, render), NOT the Dockerfile alone…
github-workflow-automation
Advanced GitHub Actions workflow automation with AI swarm coordination, intelligent CI/CD pipelines, and comprehensive repository management.
github-workflow-automation
Advanced GitHub Actions workflow automation with AI swarm coordination, intelligent CI/CD pipelines, and comprehensive repository management.
aw-author
Author, validate, and improve GitHub Agentic Workflow (gh-aw) markdown files. Use when the user wants to create a new workflow, validate an existing workflow, improve a workflow, or debug workflow issues. Triggers on: "aw-author", "agentic workflow", "gh-aw workflow", "workflow markdown", "workflow frontmatter"…
aw-daily
Fully autonomous daily pipeline for the aw-author plugin. Executes intelligence research (web search + GitHub activity queries), posts to Discussions, performs gap analysis against reference files, creates issues, implements changes on develop branch, creates PR, requests review, and auto-merges. Designed for…